Yuhong Group Co., Ltd. supplies ASTM A269 TP316L welded tubing alongside shell-and-tube heat exchangers, pressure vessels, air-cooled units, U-bend tubes, finned tubes, tube sheets, baffles, and dished heads. Our tube mill operates under the same quality system as our heat exchanger fabrication line, giving us an unusual vantage point: we know how a tube behaves after it is rolled, expanded, and U-bent into a bundle. That feedback loop directly informs our welding parameters and heat treatment cycles.
All values are maximum unless a range is given. The low carbon content (0.035% max) is the defining feature—it suppresses chromium carbide precipitation in the 427-816°C sensitization range, which is why TP316L is preferred over standard TP316 for welded tube bundles.
| Element | TP316L |
|---|---|
| Carbon (C) | 0.035 max |
| Manganese (Mn) | 2.00 max |
| Phosphorus (P) | 0.045 max |
| Sulfur (S) | 0.030 max |
| Silicon (Si) | 1.00 max |
| Chromium (Cr) | 16.0-18.0 |
| Nickel (Ni) | 10.0-15.0 |
| Molybdenum (Mo) | 2.00-3.00 |
Under ASTM A269, every welded tube must receive either a hydrostatic test or a non-destructive electric test (eddy current). Our production route applies 100% online eddy current testing to the weld zone before annealing, then hydrostatic testing after final finishing.
The tube is supplied in the heat-treated condition—solution annealed at no less than 1040°C and rapidly quenched. For welded TP316L, this step is not optional: the weld and heat-affected zone must be fully recrystallized to restore corrosion resistance across the joint.
| Parameter | Range |
|---|---|
| Outside Diameter | 6 mm - 114.3 mm |
| Wall Thickness | 0.8 mm - 3.05 mm |
| Length | 3,500 mm - 7,500 mm (custom available) |
| Grades Offered | TP304/304L, TP316/316L, TP321 |
| Surface Finish | Bright annealed, pickled, polished |
Beyond tube supply, Yuhong fabricates U-bend tubes (with post-bend stress relief), finned tubes, tube bundles, tube sheets, and baffles. This means your bundle components arrive from one production chain with consistent material traceability.
ASTM A269 TP316L tubing is specified for general corrosion-resisting and low- or high-temperature service. Typical uses include:
Why specify TP316L instead of TP316 for welded heat exchanger tubing?
The 0.035% carbon maximum in TP316L prevents sensitization during welding. TP316 (0.08% C max) can precipitate chromium carbides in the weld HAZ, creating a narrow band that is vulnerable to intergranular corrosion in aggressive media.
What does "welded" mean in the context of ASTM A269?
It means the tube is formed from strip and longitudinally welded, then solution annealed. The weld is not left in the as-welded condition. Eddy current or hydrostatic testing is mandatory on every length.
How do I verify the tube has been properly annealed?
Hardness testing is the practical field check. A reading above 90 HRB (or 192 HBW) indicates the solution treatment may be incomplete. Full verification requires metallographic examination for recrystallized grain structure.
